|
|||||
|
|
Evaluation of Construction Practices That Influence the Bond Strength at the Interface between Pavement Layers |
|
| Authors: | Laith Tashman Kitae Nam Tom Papagiannakis Kim Willoughby Linda Pierce Tom Baker |
| Affiliation: | 1Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of Jordan, Amman 99164, Jordan (corresponding author). E-mail: ltashman@wsu.edu 2WCAT Manager and Research Associate, Dept. of Civil and Environmental Engineering, Washington State Univ., Pullman, WA 99164-2910. E-mail: knam@wsu.edu 3Professor and Chair, Dept. of Civil and Environmental Engineering, Univ. of Texas-San Antonio, San Antonio, TX 78249. E-mail: at.papagiannakis@utsa.edu 4Research Manager, Construction, Materials, Bridges and Structures, and Maintenance, Washington State Dept. of Transportation, Olympia, WA 98504-7372. E-mail: willouk@wsdot.wa.gov 5State Pavement Engineer, Washington State Dept. of Transportation, Tumwater, WA 98512-6951. E-mail: piercel@wsdot.wa.gov 6State Materials Engineer, Washington State Dept. of Transportation, Tumwater, WA 98512-6951. E-mail: bakert@wsdot.wa.gov |
| Abstract: | This study investigated the influence of several construction practices on the bond strength at the interface between pavement layers. These practices included the surface treatment, curing time, residual application rate, and equipment tracking. Three tests were performed for estimating the bond strength between an existing hot mix asphalt (HMA) and a newly constructed HMA overlay, namely the Florida Dept. of Transportation shear tester, the University of Texas at El Paso pull off test, and the torque bond test. Testing involved a CSS-1 type emulsion as the tack coat. The results from the three tests were statistically analyzed. Generally, milling provided a significantly better bond at the interface between the existing surface and the new overlay. Curing time had a minimal effect on the bond strength. The results indicated that the absence of tack coat did not significantly affect the bond strength at the interface for the milled sections, whereas it severely decreased the strength for the nonmilled sections. The results also showed that increasing the residual rate of tack coat did not generally affect the bond strength at the interface. |
| Keywords: | Bonding Construction management Statistics Pavements Interfaces |